Rotary pump



July 7, 1936. H. A. GARRISON ROTARY PUMP Filed NOV. 28, 1934 At'tor neus Patented July 7, 1936 I. UNITED STATES PATENT- OFFlCE Application November No. 755,156

3 Claims.

My invention relates to rotary pumps. It relates to pumps of this type which may be .-used for pumping fluids either liquid or gaseous.

Anobject of the invention is to provide a rotary pump which will have a high degree of efflciency and'at the same time will occupy only a comparatively small space.

Another object is to provide a positive displacement rotary pump. Another object is to provide a rotary pump having no end thrust. Another object is to provide a pump for universal use which is not affected by change in suction or discharge heads. Another object is to' provide a pump having no dead points such as occur in reciprocating pumps. Another object is to provide a pump which is reversible and can be run equally well in either direction. Another object is to provide a pump in which the velocity of fluid through the pump is constant for the entire rotation of a rotary piston and is the same as that in both the suction and discharge openings. Another object is to provide a construction which may be embodied in a single unit or in more than one operated by a common driving shaft. Another object is toprovide a pump in which there are no gears or intermeshing parts and no valves or other control members not carried directly by a rotatingpiston. Another object is to provide a pump which can be eifectively operated at either low or high speed. fAnother object is to provide a rotary pump having blades with a complete seal at the ends of the blades as well as at the sides thereof. Another object is to provide a rotary pump in which theblades are held a positively in working position.

' The novel features which I believeto be characteristic of my invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together. with additional objects and advantages thereof will be best understood from the following description of a specific embodiment when read in connection with the accompanying drawing, in which,-

Fig. l is a view partly in vertical section and partly in elevation after a side plate has .een removed. Fig. 2 is a view in section on the line 22 of Fig. 1. Fig. 3 is a perspective view of a blade member. Fig. 4 is a perspective view of another blade member. Fig. 5 is a perspective view of a rotary piston. Fig. 6 is an elevational view of the rotary piston.

Referring to the particular construction shown in the drawing which illustrates an embodiment of my pump in a single unit, the numeral l0 desh for a center whereby it follows as will be underpump chamber and which can be employed inignates' a driving shaft which extends through a bearing l2 carried by one side of a casing l4, the other side of which is provided with a removable plate I 6 held in place by s'crew'bolts I8 inserted in openings 20 in the casing. Mounted for rotation in the pump chamber of the casing I4 is a rotary piston 22 from one side of which a disk member 24 projects. This disk is attached in central relation to the shaft l0 and fits into a cylindrical recess in the casing in which it rotates. 10

The peripheral wall of the pump chamber is shaped in a particular manner which constitutes an important feature of the invention. The portion from a to b as shown in Fig. 1 is arcuate, the arc being a little less than and having as a 15 center the point 0 which lies in the extended central line of the shaft Ill. The portion of the peripheral wall from d to e is also arcuate, the arc being a little more than 90 and having the point 0 as a. center. The arcuate portion de lies directly opposite the arcuate portion ab but has an appreciably longer radius. The ends of the arcuate portion ab are joined respectively with the ends of the arcuate portion de by peripheral wall portions 1 and g, these latter portions being pref erably arcuate, but eccentrically disposed with relation to ab and de in such manner as to cause a gradual merging between ab and de. As shown in Fig. 1, the portions ,1 and 9 both have the point 30 stood later that the pump is strictly reversible.

At oppositepoints intermediate the portions ab and de, the casing I4 is provided with tubular extensions 26 and 28 in communication with the 35 terchangeably as intake and discharge openings. By referring to Fig. 1, it will be seen that the arc abis less than 90 by the thickness of the blade member 34 or slot in which it works, and that the arc de is greater than 90 by the thickness of the blade member or slot in which it works. The point h is a definitely located point and may be accurately determined since it is at the inter-- section of the perpendicular bisectors of the chords of ad and be, or in other words of the lines which connect the points and the points be respectively.

The rotary piston 24 is provided with diametral slideways 30 and 32 crossing each other at right angles. The slideway 30 receives a blade member 34 while the slideway 32 receives a blade member 36. As will be understood from Figs. 3 and 4, these blade members are alike, but'in use, one of them is placed bottom up with relation to the other. The blade members are provided with 5 A notched out portions 38 which are considerably longer than the width of the blade members in order that each blade member may slide with relation to the other. The end portions of the blade members have a snug fit in the slideways, but their intermediate portions may be reduced as indicated at 40 in order to obtain easy sliding movement. The ends of the blade members as shown in Fig. 1 are preferably formed with the same curvature as the arcuate portion de in order to provide a complete seal during the entire working phase of the blade members. In connection with the tube 26, the wall portion f is provided with a port 42 which extends substantially for the length of this wall portion. In connection with the tube 28, the wall portion g is provided with a port 44 which extends substantially for the length of this wall portion.

The operation and advantages of my invention will be apparent in connection with the foregoing description and the accompanying drawing. The fluid to .be pumped may be drawn in through either the tube 26 and port 42 or through the tube 28 and port 44 according to the direction of rotation of the piston. Assuming the piston to be rotated in counterclock wise direction as shown in Fig. l, fluid will be drawn in through the tube 26 and the port 42 by the lower portion of the blade member 36 moving from the position d toward the position e. While this is occurring, the lower portion of the blade member 34 is moving from the position e toward the position b and forcing a previously drawn in charge out through the port 44 and tube 28. It will be noted that as the piston is thus rotating, the inwardly inclined wall portion g causes the blade member 34 to gradually slide and follow the outwardly inclined wall portion f, the blade member 36 at this time being held between the concentric wall portions ab and de with the ends of the blade in close engagement therewith respectively. Therefore, the blades 34 and 36 in alternation will cause fluid to be drawn in through the intake side of the casing and forced out through the discharge side thereof.

Although I have shown and described a certain specific embodiment of my invention, I am fully aware that other embodiments thereof are possible. The invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the following claims.

I claim:

1. A rotary pump comprising a casing containing a chamber provided with circumferential intake and discharge openings, a rotary piston in said chamber, and blade members slidably carried by said piston, opposite portions of the peripheral wall of said chamber being shaped on arcs having different radii and a common center in the axis of rotation of said piston, the arcuate portion of the shorter radius extending for less than 90 by the thickness of a blade member and the arcuate portion of the longer radius extending for more than 90 by the thickness of a blade member, and the intervening wall portions of said chamber being shaped on arcs having a common center symmetrically related to the respective ends of the first mentioned arcs.

2. A rotary pump comprising a casing containing a chamber provided with circumferential intake and discharge openings, a rotary piston in said chamber, and blade members slidably carried by said piston; opposite portions of the peripheral Wall of said chamber being shaped on arcs having different radii and a common center in the axis of rotation of said piston, the arcuate portion of the shorter radius extending for less than 90 by the thickness of a blade member and the arcuate portion of the longer radius extending for more than 90 by the thickness of a blade member, and the intervening wall portions of said chamber being shaped on arcs having a common center located at the intersection of perpendicular bisectors of the lines connecting the respective ends of the first mentioned arcs.

3. A rotary pump comprising a casing containing a chamber provided with circumferential intake and discharge openings, a rotatary piston in said chamber, said piston having two diametral slideways crossing each other at right angles, one piece blade members working in said slideways respectively and having reduced intermediate portions which permit them to slide independently of each other, opposite portions of the peripheral wall of said chamber being shaped on arcs having different radii and a common center in the axis of rotation of said piston, the arcuate portion of the shorter radius extending for less than 90 by the thickness of a blade member and the arcuate portion of the longer radius extending for more than 90 by the thicknes of a blade member, and the intervening wall portions of said chamber being shaped on arcs having a common center symmetrically related to the respective ends of the first mentioned arcs.

HARRY A. GARRISON. 

